JP6023130B2 - Mold inner surface measuring device - Google Patents

Description

  The present invention relates to a mold inner peripheral surface measuring device for measuring an inner peripheral surface of a tire molding mold.

  In order to manufacture a tire with good uniformity, generally a split mold is adopted as a tire vulcanization mold. This split mold includes a segment mold divided into a plurality of pieces along the circumferential direction. This segment mold has a tread segment for forming a tread pattern of a tire. By the way, it is known that RRO (Radial Run Out) of a radial tire and the unevenness | corrugation amount of the inner surface of a split mold (inner surface of a tread segment) have a high correlation. Therefore, sufficient consideration for the RRO of the split mold is indispensable. For this reason, conventionally, measurement of the inner peripheral surface of the split mold has been performed.

  A measuring device for such a measurement is disclosed in Japanese Patent Application Laid-Open No. 2002-257537. This measuring apparatus measures the amount of unevenness on the inner surface of a tread segment aligned in a cylindrical shape in use. The measuring device includes a holding body that holds a tread segment, a rotary shaft that is vertically installed at the center of the bottom of the holding body, and a non-contact distance sensor that is vertically movable on the rotary shaft. It has. The rotating shaft is rotatable around its own axis.

  Japanese Patent Application Laid-Open No. 2006-289902 discloses an apparatus for measuring the roundness of the inner surface of a tread segment. In this measuring apparatus, the distance to the inner peripheral surface of the tread segment is measured by a non-contact displacement measuring instrument. This non-contact displacement measuring device is rotationally driven by a motor. It has also been proposed that a non-contact displacement measuring device can be driven vertically by combining a bevel gear and a rack with this motor.

JP 2002-257537 A JP 2006-289902 A

  An object of the present invention is to provide a mold inner peripheral surface measuring apparatus that enables stable and continuous measurement by automatic rotation and automatic elevation of a measurement sensor.

The mold inner peripheral surface measuring apparatus according to the present invention is:
A container for fixing and holding a mold for tire vulcanization molding;
A measuring unit that can be installed inside the mold,
The container has a ring portion for gripping the outer periphery of the mold,
The measuring unit measures a distance to the inner peripheral surface of the mold, a rotational drive unit that rotates the distance sensor along the circumferential direction of the inner surface of the mold, and the distance sensor at the center of the ring unit. An elevating drive unit that elevates and lowers in a direction parallel to the axis.

  Preferably, the measurement unit includes a rotation angle detection unit that detects a rotation angle of the distance sensor, and a lift distance detection unit that detects a lift distance of the distance sensor.

Preferably, the container has a bottom on which the mold can be placed,
The measurement unit has a fixed shaft erected at the center position of the ring portion at the bottom, and a rotating cylinder disposed coaxially with the fixed shaft.
The rotary cylinder is provided with the distance sensor, the rotation drive unit, and the lift drive unit.

Preferably, the rotation driving unit has a motor for rotating the rotating cylinder,
The rotation angle detection unit has a rotary encoder that detects the rotation angle of the rotating cylinder,
The elevating drive unit includes a motor, a ball screw that is rotationally driven by the motor, and a female screw unit that is screwed into the ball screw.
The elevating distance detecting unit has a rotary encoder that detects a rotation angle of the ball screw.

  Preferably, a slip ring is provided as an electrical connection mechanism between the fixed shaft and the rotating cylinder.

Preferably, a control panel incorporating a PLC for processing an analog signal of measurement data sent from the distance sensor,
And a computer having a function of analyzing the order of data processed in the control panel.

  Preferably, the computer has a function of mapping a surface shape of an inner peripheral surface of a mold from data obtained by the distance sensor, the rotation angle detection unit, and the elevation distance detection unit.

  Preferably, the computer has a function of instructing the measurement unit of conditions for automatic measurement of the inner peripheral surface of the mold set therein.

  According to the mold inner peripheral surface measuring apparatus according to the present invention, the inner peripheral surface of a tire molding mold can be measured stably and continuously along the circumferential direction at each axial position. Can do.

FIG. 1 is a partial cross-sectional front view showing a mold inner peripheral surface measuring apparatus according to an embodiment of the present invention together with a tread segment of the mold. FIG. 2 is a left side view of the mold inner peripheral surface measuring apparatus of FIG. FIG. 3 is a block diagram showing a mold inner peripheral surface measuring apparatus including means for calculating measurement data. FIG. 4 is a waveform diagram showing an example of the result of measurement by the mold inner peripheral surface measuring apparatus of FIG.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  A mold inner circumferential surface measuring device (hereinafter also simply referred to as a measuring device) 2 shown in FIG. 1 includes a container 4 and a measuring unit 6. Fixed by the container 4 is a tread segment TS of a tire vulcanization mold to be measured. A plurality of tread segments TS are arranged in a cylindrical shape in use.

  The container 4 has a ring portion 8 that grips the outer periphery of the tread segment TS and a bottom portion 10 on which the tread segment TS is placed. The ring portion 8 has a cylindrical inner peripheral surface. The bottom 10 has a top surface on a plane. The ring portion 8 and the bottom portion 10 may be integrally formed or may be connected after being formed separately.

  The measurement unit 6 includes a distance sensor 12 that measures the distance to the inner peripheral surface of the tread segment TS. The measuring unit 6 is attached to the center of the bottom 10. The bottom 10 is provided with a positioning block 11 for adjusting the position in the horizontal plane of the measuring unit 6 installed. The measuring unit 6 is detachably attached to the positioning block 11. The measuring unit 6 can be adjusted by the positioning block 11 so as to be positioned at the center of the ring unit 8.

  The distance sensor 12 can be rotated along the circumferential direction of the inner circumferential surface of the tread segment TS. As the distance sensor 12, a non-contact type laser displacement meter can be used as in this embodiment. The distance sensor 12 measures the distance to the inner peripheral surface of the tread segment TS, and the distance from the rotation axis of the distance sensor 12 (the center axis of the fixed shaft 16 to be described later) to the distance sensor 12 is added to this. The radius of the inner peripheral surface of the tread segment TS is obtained. This radius acquisition method is also introduced in the aforementioned Japanese Patent Application Laid-Open No. 2002-257537.

  The measurement unit 6 has a support unit 14 for supporting the distance sensor 12. The support portion 14 has a fixed shaft 16 and a rotating cylinder 18. The fixed shaft 16 is vertically detachably installed at the center position of the ring portion 8 in the bottom portion 10. The fixed shaft 16 has a cylindrical shape. The rotary cylinder 18 is coaxially fixed to the fixed shaft 16 via a bearing 20. The rotary cylinder 18 is rotatable around the central axis of the fixed shaft 16. The rotating cylinder 18 has a cylindrical shape.

  A distance sensor 12 is attached to the rotary cylinder 18 via a guide rail 22, a slide block 24 and a support arm 26. The guide rail 22 is fixed to the rotary cylinder 18. The guide rail 22 extends in the direction of the central axis of the fixed shaft 16, that is, the direction parallel to the rotational axis of the rotary cylinder 18. A slide block 24 is engaged with the guide rail 22 so as to be movable up and down in the longitudinal direction of the guide rail 22. The support arm 26 is attached to the slide block 24. The distance sensor 12 is attached to the support arm 26. Thereby, the distance sensor 12 can be moved up and down in a direction parallel to the rotation axis of the rotary cylinder 18. The illustration of the distance sensor 12 is omitted in FIG.

  A rotation driving unit 28 for rotating the distance sensor 12 around the axis of the fixed shaft 16 is attached to the rotary cylinder 18. The rotation driving unit 28 can rotate the rotating cylinder 18 around the axis of the fixed shaft 16. The rotation drive unit 28 also rotates integrally with the rotary cylinder 18. The rotation drive unit 28 includes a motor 30 that rotates the rotary cylinder 18. The output shaft 30 a of the motor 30 extends parallel to the central axis of the fixed shaft 16. The output shaft 30 a is provided with a gear 34 via an electromagnetic clutch 32. The gear 34 meshes with a fixed gear 36 formed over the entire circumference on the lower end side of the fixed shaft 16. The fixed gear 36 is formed in a plane perpendicular to the central axis of the fixed shaft 16.

  When the motor 30 is driven in a state where the electromagnetic clutch 32 is connected, the rotary cylinder 18 is rotated via the rotation drive unit 28 by a reaction force from the fixed gear 36. Accordingly, the distance sensor 12 also rotates. When the electromagnetic clutch 32 is disengaged, the rotation of the rotating body 18 stops. Instead of employing the electromagnetic clutch 32, a brake may be provided. A servo motor or a stepping motor may be used.

  The rotation cylinder 18 is provided with a rotation angle detection unit 38 that detects the rotation angle of the distance sensor 12 by the rotation drive unit 28. As this rotation angle detector, a rotary encoder 38 can be employed as in the present embodiment. The main body of the rotary encoder (hereinafter referred to as a first encoder) 38 is fixed to the rotary cylinder 18 via a fixed base 37. A gear 39 is provided on the input shaft of the first encoder 38. A fixed gear 40 that engages with the gear 39 by non-backlash is provided around the fixed shaft 16. When the rotary cylinder 18 rotates, a relative rotational force is input to an input shaft (not shown) of the first encoder 38 through the engaged gears. In this way, the rotation angle of the rotating cylinder 18 is detected. As the rotational force transmission means, a timing belt may be employed instead of the gear.

  As can be seen from FIG. 2 as well, the rotary cylinder 18 is provided with an elevating drive unit 42 for elevating the slide block 24 along the guide rail 22. The elevating drive unit 42 includes a motor 44 with an electromagnetic brake, a ball screw 46 that is rotationally driven by the motor 44, and a female screw portion 48 that is screwed into the ball screw 46. The ball screw 46 is attached in a state where it cannot be raised and lowered and is rotatable. The female thread portion 48 is fixed to the slide block 24. The ball screw 46 extends parallel to the guide rail 22. The vicinity of the upper end of the ball screw 46 is supported on the upper end portion of the rotary cylinder 18 via a bearing (not shown). In FIG. 1, the ball screw 46 is not shown. FIG. 2 is a diagram for illustrating the lift drive unit 42 and a lift distance detection unit 56 described later. In FIG. 2, for easy understanding, there is a portion of the portion shown in FIG. 1 whose illustration is omitted.

  The motor 44 is attached to the upper end of the rotary cylinder 18. A gear 50 is provided on the output shaft of the motor 44 (FIG. 1). A gear 52 that is screwed into the gear 50 is provided near the upper end of the ball screw 46 (FIG. 2). With this configuration, the rotational driving force of the motor 44 is transmitted to the ball screw 46. Instead of the electromagnetic brake motor 44, a servo motor can be employed. In this case, since the servo motor includes a function as the lift distance detection unit 56, the encoder can be omitted.

  The rotary cylinder 18 is provided with a lift distance detector 56 that detects the lift distance of the distance sensor 12 by the lift driver 42. As the lift distance detection unit 56, a rotary encoder 56 can be employed as in the present embodiment. The main body of the rotary encoder (hereinafter referred to as the second encoder) 56 is attached to the rotary cylinder 18 via the fixed base 37 described above. The upper end portion of the ball screw 46 is connected to the input shaft 56 a of the second encoder 56. When the ball screw 46 is rotationally driven by the motor 44, the rotational force is directly input from the ball screw 46 to the input shaft 56 a of the second encoder 56. In this way, the rotation angle of the ball screw 46 is detected. From the rotation angle and the screw pitch of the ball screw 46, the elevation distance of the slide block 24, that is, the elevation distance of the distance sensor 12 is detected.

  As shown in FIG. 1, in the measurement unit 6, a slip ring 60 is employed as an electrical connection mechanism between the fixed shaft 16 and the rotating cylinder 18. In other words, the slip ring 60 is employed for electrical connection between each device attached to the rotary cylinder 18 and the outside. The slip ring 60 is fitted to the upper part of the fixed shaft 16. In the slip ring 60, the inner fixing portion 60i is in a fixed state, and the outer rotating portion 60o is rotatably mounted on the outer periphery of the inner fixing portion 60i via a bearing (not shown).

  The electrical connection between the rotation drive unit 28, the lift drive unit 42, the rotation angle detection unit (first encoder) 38, the lift distance detection unit 56, the control device outside the measurement unit 6, and the power source is via the slip ring 60. It is done. An electrical cable (not shown) from the rotation drive unit 28, the lift drive unit 42, the first encoder 38, and the lift distance detection unit 56 is connected to the outer rotation unit 60 o of the slip ring 60. In addition, an electric cable 62 connected to a control device outside the measuring unit 6 and a power source is connected to the inner fixing unit 60i. Of course, it is also easy to reversely configure the fixed portion and the rotating portion of the slip ring 60. That is, the outer rotating portion 60o may be fixed and electrically connected to an external control device or the like, and the inner fixing portion 60i may be rotated and electrically connected to the internal devices 28, 38, 42, and 56.

  In this way, by making the electrical connection between the rotating portion of the measuring unit 6 and the outside via the slip ring 60, it is not necessary to connect directly from each device of the measuring unit to the outside with an electric cable as in the past. For this reason, unlike the prior art, in order to prevent the cable from being entangled with the rotation of the measurement unit, it is not necessary to return to the origin by reverse rotation for each rotation of the sensor. Automatic continuous measurement is possible.

  As shown in FIG. 3, the measuring apparatus 2 includes a computer 70, a touch panel operation panel 72, and a control panel 74 equipped with a PLC (Programmable Logic Controller). In the present embodiment, the computer 70, the touch panel operation panel 72, and the control panel 74 are all arranged outside the container 4. The control panel 74 is electrically connected to the measurement unit 6 by the electric cable 62 described above. The computer 70 and the touch panel operation panel 72 are electrically connected to the control panel 74, respectively. The computer 70 has a measurement condition setting function for automatic measurement.

  Hereinafter, the measuring procedure of the inner peripheral surface of the tread segment TS by the measuring device 2 will be described. First, the measurement unit 6 is installed at the center position of the bottom 10 of the container 4. The distance from the distance sensor 12 at a plurality of arbitrary positions along the circumferential direction on the inner peripheral surface of the ring portion 8 is measured by the distance sensor 12. Each measured value is displayed on the touch panel operation panel 72. By adjusting the positioning block 11 based on the plurality of measurement values, the center axis of the fixed shaft 16 of the measurement unit 6 and the center position of the ring unit 8 are matched.

  Next, the tread segment TS is attached to the inner peripheral surface of the ring portion 8 in a posture during use. By operating the touch panel operation panel 72, the distance to the inner peripheral surface of the tread segment TS is measured while moving the distance sensor 12 in the axial direction. The movement of the distance sensor 12 in the axial direction is instructed by the touch panel operation panel 72. Based on this measured value and the movement distance of the distance sensor 12 in the axial direction, the axial center position (center position, equator position) of the inner peripheral surface of the tread segment TS is specified. An axial coordinate value (Z-axis coordinate value) indicating the axial position of the distance sensor 12 is displayed on the touch panel operation panel 72. This coordinate value is confirmed and input to the computer 70.

  The circumferential angle from the machine origin to the measurement origin is measured by moving the distance sensor 12. This measured angle (measurement origin angle) is displayed on the touch panel operation panel 72. After confirming the measurement origin angle, it is input to the computer 70.

  The boundary between the tread segments TS is detected to determine the center angle between the boundaries, that is, the center angle of each tread segment TS, and this is input to the computer 70. A predetermined measurement position in the Z-axis direction is input to the computer 70. The distance sensor 12 is returned to the machine origin (origin return). This completes the preliminary work.

  The touch panel operation panel 72 gives an instruction for automatic measurement from the computer 70 to the control panel 74. Thereby, the control board 74 operates the measurement part 6 according to this instruction | indication. The distance sensor 12 measures the distance by automatically and continuously rotating 360 ° sequentially for each measurement position in the Z-axis direction designated in advance. Measurement data from the distance sensor 12 is input to the control panel 74 as an analog electrical signal. At the same time, measurement data (rotational electrical signals) from the rotary encoders 38 and 56 of the rotation angle detection unit 38 and the lift distance detection unit 56 are input to the control panel 74 as pulse signals.

  The PLC in the control panel 74 converts the analog signal into a digital signal and processes it. The result of this processing is input to the computer 70. In the computer 70, one round (360 °) of measurement results at each measurement position in the Z-axis direction is sequentially subjected to arithmetic processing (order analysis by Fourier series analysis). After the measurement, the computer 70 confirms the calculation results at all measurement positions. Furthermore, the roundness and RRO (Radial Run Out) of the inner peripheral surface of the tread segment TS, and the 1st to 30th order amplitudes are evaluated.

  As a result of this calculation, as shown in FIG. 4, with respect to the inner peripheral surface 360 ° of the tread segment TS, the raw waveform OW, the primary waveform W1, the secondary waveform W2, the tertiary waveform W3, the primary to the 30th order. A composite waveform CW or the like is obtained. FIG. 4 shows the tread segments A, B, C, D, E, F, G, H, and I divided into nine. A circle having the average radius of the segment is denoted by the symbol AC, a circle having the largest radius is denoted by the symbol LC, and a circle having the smallest radius is denoted by the symbol SC. Although not shown, the amplitude value of each order component, the amplitude of the combined waveform, the peak position, the average diameter, and the like can be digitized and displayed. Irregularities (RRO) on the inner peripheral surface of the tread segment TS can be specified on the circumference. In the computer 70, the shape of the inner peripheral surface of the tread segment TS is mapped based on the measurement data. The mapping data of the tread segment TS can be collated with the mapping data of the tread surface of the tire vulcanized using the tread segment TS. By this collation, it is possible to analyze the change in the tread from the tread segment TS to the tire that is a molded product.

  The application mold of the measuring device 2 is not particularly limited to the split mold. According to this measuring device 2, the inner peripheral surface of the mold can be automatically and continuously measured. In this automatic continuous measurement, it is the setting of measurement conditions that requires the work of the measurer. Since the measurement results of the entire circumference at a plurality of positions along the Z-axis direction on the inner peripheral surface of the mold can be processed in a lump, the time for individually analyzing the measured data is reduced. The mold mapping data and the tire mapping data can be collated and analyzed.

  The method described above is suitable for measuring the inner peripheral surface of a tire molding die.

DESCRIPTION OF SYMBOLS 2 ... Measuring apparatus 4 ... Container 6 ... Measuring part 8 ... Ring part 10 ... Bottom part 12 ... Distance sensor 16 ... Fixed axis 18 ... Rotating cylinder 24 ... Slide block 28 ... Rotation drive unit 30 ... Motor 38 ... Rotation angle detection unit (first encoder)
42: Elevating drive unit 44: Motor 46 ... Ball screw 48 ... Female screw unit 56 ... Elevating distance detecting unit (second encoder)
60 ... Slip ring 70 ... Computer 72 ... Touch panel operation panel 74 ... Control panel

Claims (8)

A container for fixing and holding a mold for tire vulcanization molding;
A measuring unit that can be installed inside the mold,
The container has a ring portion for gripping the outer periphery of the mold,
The measuring unit measures a distance to the inner peripheral surface of the mold, a rotational drive unit that rotates the distance sensor along the circumferential direction of the inner surface of the mold, and the distance sensor at the center of the ring unit. An elevating drive unit that elevates and lowers in a direction parallel to the axis ,
The container has a bottom on which the mold can be placed;
The measurement unit has a fixed shaft erected at the center position of the ring portion at the bottom, and a rotating cylinder disposed coaxially with the fixed shaft.
In the rotating cylinder, the distance sensor, the rotation driving unit, and the elevation driving unit are installed.
The rotational drive unit has a motor for rotationally driving the rotary cylinder;
A mold inner peripheral surface measuring device in which a gear is provided on an output shaft of the motor, and the gear is engaged with a fixed gear formed over the entire circumference of the fixed shaft .   The mold inner peripheral surface measurement according to claim 1, wherein the measurement unit includes a rotation angle detection unit that detects a rotation angle of the distance sensor, and a lift distance detection unit that detects a lift distance of the distance sensor. apparatus. The rotation angle detection unit includes a first encoder that detects a rotation angle of the rotating cylinder,
The mold inner peripheral surface measuring apparatus according to claim 2, wherein a gear is provided on an input shaft of the first encoder, and the gear meshes with another fixed gear provided around the fixed shaft. The rotation angle detection unit includes a first encoder that detects a rotation angle of the rotating cylinder,
The elevating drive unit includes a motor, a ball screw that is rotationally driven by the motor, and a female screw unit that is screwed into the ball screw.
The mold inner peripheral surface measuring apparatus according to claim 2 or 3, wherein the lift distance detection unit includes a second encoder that detects a rotation angle of the ball screw. The mold inner peripheral surface measuring apparatus according to any one of claims 1 to 4 , wherein a slip ring is provided as an electrical connection mechanism between the fixed shaft and the rotating cylinder. A control panel with a built-in PLC that processes analog signals of measurement data sent from the distance sensor;
The mold inner peripheral surface measuring apparatus according to any one of claims 1 to 5, further comprising a computer having a function of analyzing the order of data processed in the control panel.   The metal mold according to claim 6, wherein the computer has a function of mapping a surface shape of an inner peripheral surface of a mold from data obtained by the distance sensor, the rotation angle detection unit, and the elevation distance detection unit. Mold inner surface measuring device. The mold inner peripheral surface measurement apparatus according to claim 6 or 7, wherein the computer has a function of instructing the measurement unit of conditions for automatic measurement of the mold inner peripheral surface set therein.

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